JPWO2007125836A1 - Method for forming Ti film - Google Patents

Abstract

A wafer W having a hole having a pore size of 0.13 μm or less and / or an aspect ratio of 10 or more is placed in a chamber (1) having a showerhead (10) functioning as a pair of parallel plate electrodes and an electrode (8). To do. While introducing a processing gas containing TiCl 4 gas and H 2 gas, high frequency power is supplied from a high frequency power source (34) to the shower head (10) to form plasma therebetween. The plasma accelerates the reaction of the processing gas to form a Ti film on the wafer. At this time, the value of power (W) of high frequency power / flow rate of TiCl 4 gas (mL / min (sccm)) is set to 67 or less.

Description

The present invention relates to a Ti film forming method for forming a Ti film on a surface of a substrate to be processed disposed in a chamber by discharging a processing gas containing TiCl ₄ gas from a shower head in the chamber.

  In the manufacture of semiconductor devices, in response to recent demands for higher density and higher integration, the circuit configuration tends to have a multilayer wiring structure. For this reason, the connection between the lower semiconductor substrate and the upper wiring layer is required. An embedding technique for electrical connection between layers such as a contact hole as a part and a via hole as a connection part between upper and lower wiring layers is important.

  It is necessary to form a good contact between the metal or alloy used for filling such a contact hole or via hole and the underlying Si substrate or poly-Si layer. For this reason, a Ti film is formed inside the contact hole or via hole prior to filling them.

  Such a Ti film has been conventionally formed by physical vapor deposition (PVD). However, with the demand for miniaturization and high integration of devices, chemicals with better step coverage (step coverage) are available. Chemical vapor deposition (CVD) is becoming increasingly used.

The following techniques have been proposed for CVD deposition of Ti films (for example, Japanese Patent Application Laid-Open No. 2004-197219 (Patent Document 1)). That is, TiCl ₄ gas, H ₂ gas, and Ar gas are used as film forming gases, these are introduced into the chamber, and high frequency power is applied to the parallel plate electrodes while the semiconductor wafer is heated by a stage heater. Thus, a Ti film is formed by plasma CVD in which the gas is turned into plasma and TiCl ₄ gas and H ₂ gas are reacted.

  However, recently, as the line width and the hole opening diameter are further reduced and the aspect ratio is increased, when the Ti film is formed by plasma CVD as in Patent Document 1, the element is caused by charge-up damage. There is a new problem that can be destroyed.

  The present invention has been made in view of such circumstances, and charge-up damage is caused when Ti is formed on a substrate to be processed having a small opening diameter and / or a high aspect ratio hole by CVD using plasma. An object of the present invention is to provide a method for forming a Ti film in which the element is not easily damaged by the above. It is another object of the present invention to provide a computer-readable storage medium for executing such a method.

In the first aspect of the present invention, a step of disposing a substrate to be processed having holes having a pore size of 0.13 μm or less and / or an aspect ratio of 10 or more in a chamber having a pair of parallel plate electrodes, and TiCl ₄ A step of supplying a high-frequency power to at least one of the parallel plate electrodes while introducing a processing gas containing a gas and H ₂ gas to form a plasma therebetween, and promoting the reaction of the processing gas by the plasma A method of forming a Ti film on the object to be processed, the method of forming a Ti film comprising: a value of power of high frequency power (W) / flow rate of TiCl ₄ gas (mL / min (sccm)) A Ti film forming method for forming a Ti film is provided.

In the first aspect, it is preferable partial pressure of greater or TiCl ₄ gas than the flow rate of TiCl ₄ gas is 12 mL / min is greater than 0.23 Pa, that the power of the RF power is less than 800W is preferable. In addition, after the Ti film is formed, NH ₃ gas, H ₂ gas, and Ar gas are preferably introduced as processing gases to perform nitriding on the surface of the Ti film without the presence of plasma.

  According to a second aspect of the present invention, there is provided a computer-readable storage medium storing a control program that operates on a computer, and the control program is configured to perform the method of the first aspect at the time of execution. A computer-readable storage medium for controlling a film forming apparatus is provided.

  In the present invention, the unit of the gas flow rate is mL / min. However, since the volume of the gas varies greatly depending on the temperature and the atmospheric pressure, the value converted into the standard state is used in the present invention. In addition, since the flow volume converted into the standard state is normally expressed by sccm (Standard Cubic Centimeter per Minutes), sccm is also written together. The standard state here is a state (STP) at a temperature of 0 ° C. (273.15 K) and an atmospheric pressure of 1 atm (101325 Pa).

The present inventors considered that the charge-up damage is caused by the electron shading effect, and in order to reduce the electron shading effect, the inventors have thought that it is effective to reduce the amount of positive ions accumulated at the bottom of the hole. In the present invention, on the basis of such knowledge, when a Ti film is formed on a substrate to be processed having holes having an aperture of 0.13 μm or less and / or an aspect ratio of 10 or more, the power (W ) / TiCl ₄ gas flow rate (mL / min (sccm)) is set to 67 or less.

That is, the raw material TiCl ₄ gas is ionized in the plasma to generate an anion of Cl. Since anions are generated by obtaining electrons, the larger the amount of TiCl ₄ , the more the electrons present in the plasma are consumed, and the electron density decreases. As described above, the decrease in the electron density in the plasma reduces the sheath voltage (ion sheath voltage) generated due to the difference between positive ions and electron mobility. Since the sheath voltage is a force that accelerates positive ions in the direction perpendicular to the hole bottom, decreasing the sheath voltage reduces the probability that positive ions will reach the bottom of the hole. ) Accumulation can be reduced. The relationship between the high frequency power (Pw), plasma potential (Vpp), and plasma density (PD) is
Pw = Vpp × PD
Can be expressed as As described above, when the TiCl ₄ gas flow rate or partial pressure increases and the electron density decreases, the resistance of the plasma itself increases and Vpp in the above equation increases. Therefore, when the high frequency power is the same, the plasma density decreases as TiCl ₄ increases, and the density of positive ions causing charge-up damage decreases. This action also reduces the accumulation of positive ions at the bottom of the hole. can do. On the other hand, when the high frequency power (Pw) is increased, the plasma density is increased when Vpp is constant in the above formula. Therefore, the density of positive ions is increased, the number of positive ions accumulated at the bottom of the hole is increased, and charge-up damage is caused. Promote. For this reason, it is better that the high frequency power is low. From the above, in the present invention, the charge-up damage due to the electronic shading effect can be reduced by setting the value of (power of high-frequency power / flow rate of TiCl ₄ gas) to a predetermined value or less, specifically 67 or less. .

FIG. 1 is a schematic cross-sectional view showing an example of a Ti film forming apparatus used for carrying out a Ti film forming method according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing an example of the structure of a semiconductor wafer applied to the present invention. FIG. 3 is a diagram for explaining a mechanism that causes charge-up damage due to an electronic shading effect.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings.

  FIG. 1 is a schematic cross-sectional view showing an example of a Ti film forming apparatus used for carrying out a Ti film forming method according to an embodiment of the present invention. The Ti film forming apparatus 100 is configured as a plasma CVD film forming apparatus that performs CVD film formation while forming plasma by forming a high-frequency electric field on parallel plate electrodes.

  The Ti film forming apparatus 100 has a substantially cylindrical chamber 1. Inside the chamber 1, a susceptor 2 for horizontally supporting a wafer W, which is a substrate to be processed, is arranged in a state of being supported by a cylindrical support member 3 provided at the center lower portion thereof. A guide ring 4 for guiding the wafer W is provided on the outer edge of the susceptor 2. In addition, a heater 5 is embedded in the susceptor 2, and the heater 5 is heated by a heater power supply 6 to heat the wafer W as a substrate to be processed to a predetermined temperature. An electrode 8 that functions as a lower electrode of a parallel plate electrode is embedded in the vicinity of the surface of the susceptor 2, and this electrode 8 is grounded. The susceptor 2 can be made of ceramics such as AlN. In this case, a ceramic heater is formed.

  A shower head 10 that also functions as an upper electrode of a parallel plate electrode is provided on the top wall 1 a of the chamber 1 via an insulating member 9. The shower head 10 includes an upper block body 10a, a middle block body 10b, and a lower block body 10c, and has a substantially disk shape. The upper block body 10a has a horizontal portion 10d that constitutes a shower head main body together with the middle block body 10b and the lower block body 10c, and an annular support portion 10e that continues above the outer periphery of the horizontal portion 10d, and is formed in a concave shape. ing. The entire shower head 10 is supported by the annular support portion 10e. Discharge holes 17 and 18 for discharging gas are alternately formed in the lower block body 10c. A first gas inlet 11 and a second gas inlet 12 are formed on the upper surface of the upper block body 10a. In the upper block body 10 a, a large number of gas passages 13 are branched from the first gas inlet 11. Gas passages 15 are formed in the middle block body 10b, and the gas passages 13 communicate with the gas passages 15 through communication passages 13a extending horizontally. Further, the gas passage 15 communicates with the discharge hole 17 of the lower block body 10c. In the upper block body 10a, a large number of gas passages 14 branch from the second gas introduction port 12. Gas passages 16 are formed in the middle block body 10 b, and the gas passage 14 communicates with these gas passages 16. Further, the gas passage 16 is connected to a communication passage 16a extending horizontally into the middle block body 10b, and the communication passage 16a communicates with a number of discharge holes 18 of the lower block body 10c. The first and second gas inlets 11 and 12 are connected to a gas line of the gas supply mechanism 20.

The gas supply mechanism 20 includes a ClF ₃ gas supply source 21 that supplies a ClF ₃ gas that is a cleaning gas, a TiCl ₄ gas supply source 22 that supplies a TiCl ₄ gas that is a Ti compound gas, and an Ar gas supply source that supplies Ar gas. 23, reducing the _{H 2} gas supply source 24 for supplying _{H 2} gas is a gas, and a NH ₃ gas supply source 25 for supplying the NH ₃ gas is a gas nitriding. The ClF ₃ gas supply source 21 has ClF ₃ gas supply lines 27 and 30b, the TiCl ₄ gas supply source 22 has a TiCl ₄ gas supply line 28, the Ar gas supply source 23 has an Ar gas supply line 29, H _{2 H 2} gas supply line 30 to the gas supply source 24, the NH ₃ gas supply source 25 NH ₃ gas supply line 30a is connected, respectively. Moreover, although not shown, it also has an N2 gas supply source. Each gas line is provided with two valves 31 sandwiching the mass flow controller 32 and the mass flow controller 32.

A TiCl ₄ gas supply line 28 extending from a TiCl ₄ gas supply source 22 is connected to the first gas introduction port 11, and a ClF ₃ gas extending from a ClF ₃ gas supply source 21 is connected to the TiCl ₄ gas supply line 28. An Ar gas supply line 29 extending from the supply line 27 and the Ar gas supply source 23 is connected. An H ₂ gas supply line 30 extending from an H ₂ gas supply source 24 is connected to the second gas introduction port 12, and the H ₂ gas supply line 30 extends from an NH ₃ gas supply source 25. The NH ₃ gas supply line 30 a and the ClF ₃ gas supply line 30 b extending from the ClF ₃ gas supply source 21 are connected. Therefore, when the process, the shower head from the first gas inlet port 11 of the shower head 10 TiCl ₄ gas from the TiCl ₄ gas supply source 22 through the TiCl ₄ gas supply line 28 together with Ar gas from the Ar gas supply source 23 10, and is discharged into the chamber 1 from the discharge hole 17 through the gas passages 13 and 15, while the H ₂ gas from the H ₂ gas supply source 24 passes through the H ₂ gas supply gas line 30 to the shower head 10. The second gas inlet 12 reaches the shower head 10 and is discharged from the discharge hole 18 into the chamber 1 through the gas passages 14 and 16. That is, the shower head 10 is a post-mix type in which TiCl ₄ gas and H ₂ gas are supplied into the chamber 1 completely independently, and these are mixed and reacted after discharge. However, the present invention is not limited to this, and a premix type in which TiCl ₄ and H ₂ are mixed and supplied into the chamber 1 may be used.

  A high frequency power supply 34 is connected to the shower head 10 via a matching unit 33, and high frequency power is supplied from the high frequency power supply 34 to the shower head 10. By supplying high-frequency power from the high-frequency power source 34, the gas supplied into the chamber 1 through the shower head 10 is turned into plasma to perform film formation.

  Further, a heater 45 for heating the shower head 10 is provided in the horizontal portion 10d of the upper block body 10a of the shower head 10. A heater power source 46 is connected to the heater 45, and the shower head 10 is heated to a desired temperature by supplying power to the heater 45 from the heater power source 46. In order to increase the heating efficiency by the heater 45, a heat insulating member 47 is provided in the concave portion of the upper block body 10a.

  A circular hole 35 is formed at the center of the bottom wall 1b of the chamber 1, and an exhaust chamber 36 is provided on the bottom wall 1b so as to protrude downward so as to cover the hole 35. An exhaust pipe 37 is connected to a side surface of the exhaust chamber 36, and an exhaust device 38 is connected to the exhaust pipe 37. By operating the exhaust device 38, the inside of the chamber 1 can be depressurized to a predetermined degree of vacuum.

  The susceptor 2 is provided with three (only two are shown) wafer support pins 39 for supporting the wafer W to be moved up and down so as to protrude and retract with respect to the surface of the susceptor 2. It is fixed to the plate 40. The wafer support pins 39 are lifted and lowered via the support plate 40 by a drive mechanism 41 such as an air cylinder.

  On the side wall of the chamber 1, a loading / unloading port 42 for loading / unloading the wafer W to / from a wafer transfer chamber (not shown) provided adjacent to the chamber 1, and a gate valve 43 for opening / closing the loading / unloading port 42, Is provided.

  The constituent parts of the Ti film forming apparatus 100 are connected to and controlled by a control unit 50 made up of a computer. In addition, the control unit 50 includes a keyboard on which a process manager manages command input to manage the Ti film forming apparatus 100, a display that visualizes and displays the operating status of the Ti film forming apparatus 100, and the like. A user interface 51 is connected. Furthermore, the control unit 50 includes a control program for realizing various processes executed by the Ti film forming apparatus 100 under the control of the control unit 50, and each component of the Ti film forming apparatus 100 according to processing conditions. A storage unit 52 storing a program for causing the unit to execute processing, that is, a recipe, is connected. The recipe may be stored in a hard disk or a semiconductor memory, or may be set at a predetermined position in the storage unit 52 while being stored in a portable storage medium such as a CDROM or DVD. Furthermore, you may make it transmit a recipe suitably from another apparatus via a dedicated line, for example. Then, if necessary, an arbitrary recipe is called from the storage unit 52 by an instruction from the user interface 51 and is executed by the control unit 50, so that the Ti film forming apparatus 100 can control the control unit 50. The desired processing is performed.

  Next, a Ti film forming method according to this embodiment in the Ti film forming apparatus 100 as described above will be described.

  In the present embodiment, for example, a semiconductor wafer having a structure shown in FIG. That is, the gate electrode 103 is formed on the silicon substrate 101 through the gate insulating film 102, the interlayer insulating film 104 and the metal wiring layer 105 are formed around and on the silicon substrate 101, and the metal wiring layer 105 and the gate electrode 103 are connected to each other. They are connected by a buried wiring 106. On the metal wiring layer 105, an interlayer insulating film 108 in which a via hole 107 is formed is formed. Further, a trench 109 is formed in the interlayer insulating film 104.

In order to form a Ti film on the wafer W having such a structure, first, the inside of the chamber 1 is adjusted in the same manner as the external atmosphere connected via the gate valve 43, and then the gate valve 43 is opened and a vacuum is formed. The wafer W having the above structure is loaded into the chamber 1 through a loading / unloading port 42 from a wafer transfer chamber (not shown). Then, the wafer W is preheated while supplying Ar gas into the chamber 1. When the temperature of the wafer W is substantially stabilized, pre-flow is performed by flowing Ar gas, H ₂ gas and TiCl ₄ gas through a preflow line (not shown) at a predetermined flow rate. Then, the film flow is switched to the film forming line while maintaining the same gas flow rate and pressure, and these gases are introduced into the chamber 1 through the shower head 10. At this time, high frequency power is applied to the shower head 10 from the high frequency power supply 34, whereby Ar gas, H ₂ gas, and TiCl ₄ gas introduced into the chamber 1 are turned into plasma. Then, the gas converted into plasma on the wafer W heated to a predetermined temperature by the heater 5 reacts to deposit Ti on the wafer W.

  Thus, when forming a Ti film by CVD in the presence of plasma, the processing conditions are conventionally determined in consideration of the film quality (electrical characteristics) of the Ti film, the film forming speed, the uniformity of the film thickness, and the like. is doing. However, recently, due to device miniaturization, it has become necessary to have a hole opening diameter of 0.13 μm or less and / or an aspect ratio of 10 or more, and it has been found that charge-up damage is likely to occur under conventional conditions. did.

  A mechanism that causes charge-up damage will be described with reference to FIG. First, when plasma is generated, the surface of the wafer W is negatively charged, a potential difference Vpp is generated between the plasma P and the silicon substrate 101, and an ion sheath S is formed between the plasma and the wafer W. The In essence, the electron e is light and moves vigorously and easily moves isotropically. The ion i is heavy and moves slowly and tends to move anisotropically. Therefore, in the ion sheath S in which an electric field of the potential difference Vpp is generated, the electrons e move in an isotropic manner with a large amount of lateral movement, and the ions i are anisotropic toward the wafer W along the electric field direction of the ion sheath S. Move with high character. Therefore, in the via hole 107 having a small opening diameter and a large aspect ratio, the electron e is difficult to reach the bottom, but the ions i are accelerated by the ion sheath S and reach the bottom of the hole, so that the bottom of the via hole 107 is positive. Charged (electronic shading effect). On the other hand, since the trench 109 is wide, electrons e that move isotropically easily reach the bottom thereof. For this reason, a potential difference is generated between the bottom of the via hole 107 and the bottom of the trench 109, and an electric field is generated in the gate insulating film 102. As the opening diameter of the via hole 107 is smaller and the aspect ratio is larger, such a phenomenon becomes more prominent, the potential difference between the bottom of the via hole 107 and the bottom of the trench 109 becomes larger, and a strong electric field is applied to the gate insulating film 102. In some cases, dielectric breakdown occurs in the gate insulating film 102 and the element is destroyed (charge-up damage). Such char-up damage has hardly occurred in the past, but it has come to occur to a degree that cannot be ignored when the hole opening diameter is 0.13 μm or less and / or the aspect ratio is 10 or more.

As a result of repeated studies on methods for effectively eliminating such charge-up damage, the present inventors have found that it is effective to reduce the amount of accumulation by reducing the driving force that positive ions reach the bottom of the hole. I found out. For this purpose, it has been found that the value of power (W) of high frequency power / flow rate of TiCl ₄ gas (mL / min (sccm)) should be 67 or less. That is, the source gas TiCl ₄ gas is ionized in the plasma to generate Cl anions, but the anions obtain and generate electrons, so the more TiCl ₄ is consumed, the more electrons in the plasma are consumed. As a result, the electron density decreases. As described above, the decrease in the electron density in the plasma reduces the sheath voltage (ion sheath voltage) generated due to the difference between positive ions and electron mobility. Since the sheath voltage is a force that accelerates positive ions in the direction perpendicular to the bottom of the hole (via hole 107), the probability that positive ions will reach the bottom of the hole is reduced by decreasing the sheath voltage. Accumulation of positive ions (positive charges) can be reduced. The relationship between the high frequency power (Pw), plasma potential (Vpp), and plasma density (PD) is
Pw = Vpp × PD
Can be expressed as As described above, when the TiCl ₄ gas flow rate or partial pressure increases and the electron density decreases, the resistance of the plasma itself increases and Vpp in the above equation increases. Therefore, when the high frequency power is the same, the plasma density decreases as TiCl ₄ increases, and the density of positive ions causing charge-up damage decreases. This action also reduces the accumulation of positive ions at the bottom of the hole. can do. On the other hand, when the high frequency power (Pw) is increased, the plasma density is increased when Vpp is constant in the above formula. Therefore, the density of positive ions is increased, the number of positive ions accumulated at the bottom of the hole is increased, and charge-up damage is caused. Promote. For this reason, it is better that the high frequency power is low. Thus, from the viewpoint of suppressing the charge-up damage, it is better that the TiCl ₄ flow rate or partial pressure is high and the high frequency power is low. From such a viewpoint, the value of (power of high frequency power / flow rate of TiCl ₄ gas) Is less than or equal to a predetermined value. The flow rate of TiCl ₄ gas, which is a conventional standard condition: 12 mL / min (sccm), and the high frequency power: 800 W are used as references, and the TiCl ₄ gas flow rate is greater than 12 mL / min or the partial pressure of TiCl ₄ gas is 0.23 Pa. It was found that charge-up damage does not occur due to the electronic shading effect when the power is set to a range that is larger and the high-frequency power is smaller than 800 W. Therefore, based on this, the value of the power of high frequency power (W) / flow rate of TiCl ₄ gas (mL / min (sccm)) is set to 67 or less.

Therefore, in this case, it is preferable that the flow rate of TiCl ₄ gas is greater than 12 mL / min (sccm), or the partial pressure of TiCl ₄ gas is greater than 0.23 Pa and the high frequency power is less than 800 W. More preferably, the flow rate of TiCl ₄ gas is 12 to 20 mL / min (sccm) or the partial pressure of TiCl ₄ gas is 0.23 to 17.54 Pa, and the high frequency power is less than 200 to 800 W. From such a viewpoint, the preferable range of the value of the power (W) of the high frequency power / the flow rate of the TiCl ₄ gas (mL / min (sccm)) is 10 to 67.

  Other process conditions may be the same as those for forming a Ti film by normal plasma CVD, and the following conditions are exemplified.

Frequency of high frequency power: 300 kHz to 27 MHz
Susceptor temperature: 300-650 ° C
Ar gas flow rate: 500 to 2000 mL / min (sccm)
H ₂ gas flow rate: 1000 to 5000 mL / min (sccm)
Chamber pressure: 133 to 1333 Pa (1 to 10 Torr)
The time for forming the Ti film is appropriately set according to the film thickness to be obtained.

After the Ti film is formed as described above, the Ti film may be subjected to nitriding treatment as necessary. In this nitriding treatment, after the Ti deposition step is finished, the TiCl ₄ gas is stopped, the H ₂ gas and the Ar gas are kept flowing, and the inside of the chamber 1 is heated to an appropriate temperature while the NH 3 gas is used as a nitriding gas. Flow ₃ gases. At the same time, high-frequency power is applied from the high-frequency power source 34 to the shower head 40 to turn the processing gas into plasma, and the surface of the Ti thin film formed on the wafer W is nitrided with the plasma-ized processing gas. In the Ti film formation process, Ti film may not be deposited on the sidewalls of contact holes and via holes. In this case, since conduction is not established between the top and bottom of the hole, plasma is generated during nitriding. Charge-up damage may occur. From the viewpoint of avoiding this, it is preferable to perform nitriding without forming plasma.

  Preferred conditions for the nitriding treatment are as follows.

Frequency of high frequency power: 300 kHz to 27 MHz
High frequency power: 200-1500W
Susceptor temperature: 300-650 ° C
Ar gas flow rate: 2000 mL / min (sccm) or less, preferably 800 to 2000 mL / min (sccm)
H ₂ gas flow rate: 1500-4500 mL / min (sccm)
NH ₃ gas flow rate: 500 to 2000 mL / min (sccm)
Chamber pressure: 133 to 1333 Pa (1 to 10 Torr)
This step is not essential, but is preferably performed from the viewpoint of preventing oxidation of the Ti film.

  After the Ti film is formed or nitrided, the inside of the chamber 1 is adjusted in the same manner as the external atmosphere connected via the gate valve 43, then the gate valve 43 is opened and a wafer (not shown) is connected via the loading / unloading port 42. The wafer W is unloaded into the transfer chamber.

In this manner, after forming the Ti film and performing nitriding treatment on a predetermined number of wafers as necessary, the chamber 1 is cleaned. In this process, ClF ₃ gas is introduced into the chamber 1 from the ClF ₃ gas supply source 21 through the ClF ₃ gas supply lines 27 and 30b in a state where no wafer is present in the chamber 1, and the shower head 10 is set in an appropriate state. It is performed by performing dry cleaning while heating to a temperature.

The present invention is not limited to the above embodiment and can be variously modified. For example, in the above embodiment, the case where TiCl ₄ gas, H ₂ gas, and Ar gas are simultaneously supplied to perform plasma CVD has been described, but the present invention is not limited to this. For example, an SFD process in which a first step of supplying TiCl ₄ gas, H ₂ gas, and Ar gas and a second step of supplying H ₂ gas and Ar gas may be used. Instead, an ALD process that alternately performs a first step of supplying TiCl ₄ gas and Ar gas and a second step of supplying H ₂ gas and Ar gas may be used. In the ALD process, plasma may be generated only in the second step. Furthermore, the substrate to be processed is not limited to a semiconductor wafer, but may be another substrate such as a liquid crystal display (LCD) substrate.

  The present invention is applicable to a Ti film forming method for forming a Ti film on the surface of a substrate to be processed.

Claims (5)

Disposing a substrate to be processed having a hole having a pore size of 0.13 μm or less and / or an aspect ratio of 10 or more in a chamber having a pair of parallel plate electrodes;
Supplying a high frequency power to at least one of the parallel plate electrodes while introducing a processing gas containing TiCl ₄ gas and H ₂ gas to form plasma therebetween,
Accelerating the reaction of the processing gas with the plasma to form a Ti film on the object to be processed;
The Ti film is formed by setting the value of the power of high frequency power (W) / flow rate of TiCl ₄ gas (mL / min (sccm)) to 67 or less. The method of forming a Ti film according to claim 1, wherein the flow rate of TiCl ₄ gas is greater than 12 mL / min or the partial pressure of TiCl ₄ gas is greater than 0.23 Pa.   The method for forming a Ti film according to claim 1, wherein the power of the high-frequency power is smaller than 800W. The method for forming a Ti film according to claim 1, wherein after the Ti film is formed, NH ₃ gas, H ₂ gas, and Ar gas are introduced as processing gases to perform nitriding treatment on the surface of the Ti film without the presence of plasma. A computer-readable storage medium storing a control program that runs on a computer,
The computer-readable storage medium that, when executed, controls the film forming apparatus so that the method according to claim 1 is performed.

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